We conducted a 3‐year experiment on the effects of otter trawling on benthic habitat and communities on a sandy‐bottom ecosystem of the Grand Banks of Newfoundland that has supported commercial fisheries. Each year, three 13‐km‐long corridors were trawled 12 times with an Engel 145 otter trawl, creating a disturbance zone 120–250 m wide. Using a variety of oceanographic instruments, measurements were made before and after trawling to document effects. Trawling had no detectable effect on sediment grain size. Tracks made by trawl doors were readily visible on the sea floor immediately after trawling and 10 weeks later; in some cases they were still faintly visible after 1 year. Acoustic data indicated that trawling increased the topographic relief or roughness of surficial sediments and changed small‐scale biogenic sediment structures down to depths of 4.5 cm. Video observations in trawled corridors revealed that organisms and shells tended to be organized into linear features parallel to the corridor axis. They also demonstrated that trawling reduces both surficial biogenic sediment structure and the abundance of flocculated organic matter; untrawled sediments had a hummocky, mottled appearance, whereas trawled sediments were smoother and cleaner. These changes combined to give the trawled corridors a lighter appearance in color. It appears that the physical effects of otter trawling observed in this experiment are moderate and that recovery occurs in about a year. The biological effects of this experimental trawling have yet to be examined. Efectos del Arrastre Experimental en las Propiedades de Sedimentos Superficiales de un Ecosistema de Fondo Arenoso de los Grande Bancos de Terranova Un experimento de tres años sobre los efectos del arrastre en hábitat bentónico y sus comunidades fue realizado en un ecosistema arenoso que soporta pesquerías comerciales de los Grandes Bancos de Terranova. Cada año, tres corredores de 13 km de largo fueron arrastrados 12 veces con una red de arrastre Engel, creando una zona de perturbación de 120‐250 m de ancho. Para documentar los efectos se realizaron mediciones antes y después del arrastre usando una variedad de instrumentos oceanográficos. Los arrastres no tuvieron efectos detectables en el tamaño de grano del sedimento. Las marcas hechas por las puertas del arrastre fueron fácilmente visibles en el fondo inmediatamente después del arrastre y hasta 10 semanas después; en algunos casos las marcas fueron visibles después de un año. Los datos acústicos indican que el arrastre incrementa el relieve topográfico o la aspereza del sedimento superficial y cambia las estructuras biogénicas de pequeña escala del sedimento hasta una profundidad de 4.5 cm. Observaciones de video en corredores de arrastre revelan que los organismos y conchas tienden a estar organizados en forma lineal y paralelos a los ejes del corredor. Los videos también demostraron que el arrastre reduce tanto la estructura biogénica superficial del sedimento como la abundancia de materia orgánica floculada; sediment...

Surveys for lobster larvae in offshore waters of the north-eastern Gulf of Maine in 1983Maine in , 1987Maine in and 1989 confirm that local hatching occurs mainly at depths <100 m over the banks, including Georges and Browns Banks. Detailed studies in the vicinity of Georges Bank in late July of both 1987 and 1989 indicate that the first and second moult stages were located primarily over the bank whereas stages III and IV lobster were collected both over and off the bank. At times stage IV lobster were more abundant off the bank than over it. The condition of stage III and IV lobster, as measured by a lipid index, was better off than over Georges Bank in 1988 and 1989 indicating a possible physiological advantage to being off the bank. In addition, the higher surface temperatures off Georges Bank would shorten larval development time to settlement. To determine the probable hatch sites of stage IV lobster collected off of Browns Bank in 1983 and off of Georges in 1987 and 1989, a 3-D circulation model of the Gulf of Maine was used to simulate larval lobster drift backwards in time. In all cases, areas off Cape Cod, MA, and off Penobscot Bay, ME were suggested as the source of the larvae, although most of the larval trajectories never reached these near-shore waters that are well-known, larval hatching areas. The model-projected larval release times match most closely the observed inshore hatch off Massachusetts but model uncertainties mean that coastal Maine cannot be ruled out as a source. Georges

A 3-year otter trawling experiment was conducted on a deepwater (120–146 m) sandy bottom ecosystem on the Grand Banks of Newfoundland that had not experienced trawling for at least 12 years. The benthic macrofauna were sampled before and after trawling and in reference areas. The 200 grab samples collected contained 246 taxa, primarily polychaetes, crustaceans, echinoderms, and molluscs. Biomass was dominated by propeller clams (Cyrtodaria siliqua) and sand dollars (Echinarachnius parma), while abundance was dominated by the polychaete Prionospio steenstrupi and the mollusc Macoma calcarea. The most prominent feature of the data was a natural decline in the total number of species, the total abundance, and the abundance and biomass of selected species between 1993 and 1995. The only immediate effect of trawling was seen in 1994 when the abundance of 13 species, the biomass of 11 species (mostly polychaetes), and the total abundance per grab were significantly lower. There was little evidence of long-term trawling effects. When trawling disturbance was indicated, it appeared to mimic natural disturbance, shifting the community in the same direction in multidimensional scaling ordination; no distinctive trawling signature was observed. However, the results of this experiment should not be uncritically extrapolated to the impacts of commercial trawling.

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Six species of the weevil genus Orchidophilus Buchanan are recognized: O. epidendri (Murray) comb. n. (=Acythopeus genuinus Pascoe syn. n., =Baris orchivora Blackburn syn. n., =Apotomorhinus orchidearum Kolbe syn. n.), O. aterrimus (Waterhouse), O. eburifer (Pascoe) comb. n. (=Acythopeus gilvonotatus Barber syn. n.), O. peregrinator Buchanan, O. ran Morimoto and O. insidiosus Prena sp. n. These species appear to be native to Indonesia, Malaysia, the Philippines and Singapore but are dispersed frequently with orchid cultivars by global trade. Orchidophilus aterrimus has been intercepted most frequently and now is established in several Indo-Pacific regions outside its native range. Nearly as common as, and occasionally confused with, the former is O. epidendri. Orchidophilus ran is of some significance in Japan and Korea, while O. peregrinator, O. eburifer and O. insidiosus were intercepted occasionally at scattered locations before 1970. An identification key for the six species is provided. Lectotypes are designated for Baridius aterrimus Waterhouse, Acythopeus genuinus Pascoe, Baris orchivora Blackburn and Apotomorhinus orchidearum Kolbe; a neotype is designated for Centrinus epidendri Murray.